The mug itself cost $9.99 and you get to take it home with you. It is refillable but you are charged for the refill. The perk is that you will be charged for a 12oz but get a 16oz drink. The only problem with this is that you have to lug that glass mug around with you everywhere you go to get the deal. One of my favorite memories of the cruise is the men in the breakfast buffet line with their beer mugs in hand.